Could be better ... Noté 2 sur 5 étoiles
Update Scanner would be much better if it were possible to select a portion of the page to scan, rather than selecting the number of characters in the page that must change before it notifies the user. The problem with detecting the "number of characters that have changed" is that I get far too many false positives, because the part of the page I want to check may not change, but other parts have changed so it notifies me about those other changes ... which I could not care less about!
Check4Change 'correctly' detects changes only in the portion of the page that you select, so in this respect it is a better tool than Update Scanner. Unfortunately Check4Change does not remember to check pages when their tabs are closed, nor does it remember to check them again after a restart, so it fails miserably on these points, thus making it useless to me.
I need a tool that checks my pre-defined pages reliably whenever the browser is open. The ideal solution for my needs would be a tool that remembers to check for changes any time the browser is running, and it would check only in the specific part of the page that I specify -- such as the price on a product page for example. Then I could use it to automatically check any price on any web page, and when that price changes I would be alerted automatically.
The person who combines the capabilities of Check4Change and Update Scanner will have a winner. But as it is now (April 03, 2013) both of these addons fail to provide what I need most.
At least Update Scanner works after a restart and when my pages are not open in tabs, so that's why I continue to use it instead of Check4Change ... but with all the false positives it is frustrating to deal with to say the least.